package com.Tokiu.filter;

import com.Tokiu.common.BaseContext;
import com.Tokiu.common.R;
import com.alibaba.fastjson.JSON;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否登录
 */

@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {

    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER=new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request=(HttpServletRequest) servletRequest;
        HttpServletResponse response=(HttpServletResponse) servletResponse;


        //1、获取本次请求的URI
        String requestURI = request.getRequestURI();

        log.info("拦截到请求：{}",requestURI);

        //定义不需要处理的请求路径
        String[] urls=new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**"
        };


        //2、判断本次请求是否需要处理

        boolean check = check(urls, requestURI);

        //3、如果不需要处理，则直接放行

        if(check)
        {
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

        //4、判断登录状态，如果已登录则直接放行

        if(request.getSession().getAttribute("employee")!=null)
        {
            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("employee"));

            Long empId = (Long)request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);
            filterChain.doFilter(request,response);
            return;
        }

        //5、如果未登录则返回未登录结果

        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;

    }


    /**
     * 路径匹配，检查本次请求是否放行
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls,String requestURI){
        for(String url:urls){
            boolean match = PATH_MATCHER.match(url, requestURI);

            if(match)
            {
                return true;
            }
        }

        return false;
    }
}
